https://dod.defense.gov/Portals/1/Documents/pubs/DoD%20Law%20of%20War%20Manual%20-%20June%202015%20Updated%20Dec%202016.pdf?ver=2016-12-13-172036-190
I think this pretty much lays it out….
I agree Anon. An expected death after a long full life should be celebrated not mourned.
same